The future James Webb Space Telescope (JWST), developed jointly by the American, European and Canadian space agencies (NASA, ESA and CSA), is scheduled for launch in 2013. The near-infrared spectrograph NIRSpec will be a major element of its instrument suite and is built by EADS Astrium for ESA. NIRSpec is a multiobject spectrograph allowing astronomers to obtain the spectra of more than one hundred objects in a single exposure. NIRSpec is currently under construction and, when finished, will be subjected to a stringent onground test campaign to verify its performance. These tests are conducted in collaboration with ESA. A rapid and reliable system to handle and analyse the data is crucial in this phase as the time available to run the cryogenic tests is limited. To facilitate this process we are developing a toolbox of dedicated algorithms and interactive visualisation modules. These standalone modules form the basis of the Instrument Quick Look Analysis and Calibration (IQLAC) software. Individual workflows, optimized for specific tests, can then be generated efficiently using this toolbox. Furthermore, this set of dedicated algorithms will provide a reference frame for the development of the operational data processing software by ESA.